Method for operating a hearing aid, and hearing aid

ABSTRACT

A method for operating a hearing aid which has an auditory canal microphone for capturing sound in the auditory canal of the wearer and an own voice recognition unit for carrying out an adaptive own voice recognition. Sound in the auditory canal is captured by the auditory canal microphone and a signal that corresponds to the sound is output by the auditory canal microphone, and training of the adaptive own voice recognition is controlled only based on the signal output by the auditory canal microphone. A corresponding hearing aid configured to carry out the method.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the priority, under 35 U.S.C. § 119, of Germanpatent application DE 10 2020 213 051.5, filed Oct. 15, 2020; the priorapplication is herewith incorporated by reference in its entirety.

FIELD AND BACKGROUND OF THE INVENTION

The invention relates to a method for operating a hearing aid comprisingan auditory canal microphone, wherein sound in the auditory canal of thewearer is captured by the auditory canal microphone and a signal thatcorresponds to the sound is output by the auditory canal microphone.Moreover, the invention relates to such a hearing aid.

Hearing aids, particularly for the hard of hearing, are provided indifferent types in order to accommodate the individual needs of thewearer. By way of example, hearing aids are embodied as behind-the-ear(“BTE”) hearing aids, as receiver-in-canal (“RIC”) hearing aid or asin-the-ear (“ITE”) hearing aids.

Hearing aids comprise at least one electroacoustic transducer, inparticular a microphone, which is used to capture (airborne) sound fromthe surroundings of the wearer. A corresponding signal output by thetransducer is processed by a signal processing unit in respect of theneeds of the wearer, said signal being amplified in particular. Theprocessed signal is transmitted to a receiver (loudspeaker), and outputby the latter as sound into the auditory canal or at the eardrum of thewearer.

The wearer (user) of a hearing aid perceives their own voice differentlyto the way it is recorded by the microphone of the hearing aid, whichtypically captures airborne sound, on account of the body-borne soundand/or—providing the hearing aid seals the auditory canal of the wearerin part or in full—on account of the occlusion effect.

Consequently, so that the wearer considers the perception of their ownvoice and of external audio sources to be normal, the own voice of thewearer and other external audio sources have to be processeddifferently. To this end, the own voice of the wearer needs to berecognized in a first step.

By way of example, a method for recognizing the own voice of the weareris known from EP 3 451 705 A1. In the method described therein forquickly recognizing the own voice of a hearing-aid wearer, the audiosignals of at least a first microphone and a second microphone are used.The audio signal from the first microphone is filtered by a first filterwhich attenuates the own voice of the hearing-aid wearer. Furthermore,the audio signal of the second microphone is damped by a second filterwhich attenuates an external audio source. The output signals of the twofilters are compared to one another and the voice of the hearing-aidwearer is recognized based on the result. In this case, the first filtercan be an adaptive filter. By way of example, the first filter isrealized by an adaptive algorithm which adaptively ascertains the filterparameters of the first filter such that these filter parameters can beascertained during a training with the own voice of the hearing-aidwearer. Here, training is implemented either within the scope of fittingat the hearing-aid acoustician or by the wearer themselves during theirnormal voice activity, with additional reference information aboutspeech activity present being transmitted, for example by way of aremote control or a smartphone.

Furthermore, DE 10 2016 203 987 A1 has disclosed a method for operatinga hearing aid, in which a noise recorded by means of a microscope isanalyzed in respect of the correspondence thereof to the voice of thehearing-aid wearer. A feature value is output as a result of theanalysis and compared to a threshold. Here, the threshold is set in amanner dependent on the surroundings, i.e., in accordance withascertained surroundings. The threshold is set for the respectivesurroundings situation either within the scope of a fitting session atthe acoustician, in a specific calibration operation or during normaloperation of the hearing aid.

DE 10 2005 032 274 A1 illustrates a hearing aid and a method for theoperation thereof. To detect the own voice of the hearing-aid wearer, asound signal of a first microphone for recording an ambient sound and asound signal of a second microphone for recording an auditory canalsound are analyzed. To this end, the levels of the two sound signals arecompared to one another and the presence of the own voice is deducedbased on the comparison.

EP 3 005 731 B1 has described a method for operating a hearing aidcomprising a surround microphone, a signal processing unit, a receiverand an auditory canal microphone. Here, the audio signal of the surroundmicrophone, which is processed by the signal processing unit with afilter, is filtered with a transfer function that comprises at least onetransfer function from an output of the receiver to an input of theauditory canal microphone when the hearing aid is activated and worn inan auditory canal of the user. A difference between the audio signalrecorded by the auditory canal microphone and the filtered signal iscalculated and the presence of an own voice of the user is recognizedbased on the difference.

US 2019/0075406 A1 has disclosed a hearing aid comprising an auditorycanal microphone to be worn on or in the auditory canal of the user, anda further behind-the-ear microphone arranged on or behind an ear of theuser. Here, the own voice of the user is recognized if a sound pressurelevel at the auditory canal microphone is at least 2.5 dB greater thanthat at the behind-the-ear microphone. The hearing aid comprises abeamformer filter unit made of an adaptive algorithm for providing aspatially filtered signal. In this case, the beamformer filter unit maycomprise a predefined and/or adaptively updated own speech beamformer,which is focused on the mouth of the user.

SUMMARY OF THE INVENTION

The invention is based on the object of specifying a method foroperating a hearing aid, in which training of the own voice recognitionis implemented as effectively as possible and/or as comfortably aspossible for the wearer of the hearing aid. Moreover, such a hearing aidshould be specified.

In respect of the method, the object is achieved according to theinvention by the features of the claims. In respect of the hearing aid,the object is achieved according to the invention by the features of theclaims. Advantageous developments and configurations are the subjectmatter of the dependent claims. Here, the explanations in the context ofthe method also apply analogously to the hearing aid, and vice versa.

The method serves for the operation of a hearing aid. Here, such ahearing aid is understood to mean a device for treating a person whosehearing is damaged or impaired and who wears the device—expedientlycontinuously or for most of the time—to compensate a hearing deficiency.By way of example, said device is embodied as a behind-the-ear hearingaid or as an in-the-ear hearing aid.

The hearing aid comprises an auditory canal microphone for capturingsound, in particular airborne sound, in the auditory canal of the wearer(user) of the hearing aid. In particular, the auditory canal microphoneis provided and set up to be introduced into and worn in the auditorycanal of the user when the hearing aid is used. If sound in the auditorycanal is captured by the auditory canal microphone, the latter outputs asignal corresponding to the sound, i.e., a signal representing thesound. Below, this signal is also referred to as auditory canal signal.

Expediently, the hearing aid furthermore comprises a second microphone,specifically a surround microphone, for capturing sound from thesurroundings of the wearer. In a manner analogous to the auditory canalmicrophone, the surround microphone outputs a further signal, which isreferred to as surround signal below and which corresponds to thecaptured surround sound, if sound from the surroundings of the wearer ofthe hearing aid is captured by the surround microphone.

Furthermore, the hearing aid has an own voice recognition unit. By wayof example, the latter is part of a control unit or, alternatively, itis embodied as a unit separate from the control unit. By way of example,the own voice recognition unit is realized as an integrated circuit. Theauditory canal signal and/or the surround signal are transmitted fromthe auditory canal microphone and from the surround microphone,respectively, to the own voice recognition unit or to the controlapparatus.

The own voice recognition unit serves to carry out an analysis of thesurround signal and/or of the auditory canal signal to the effect ofwhether or not the own voice of the wearer is present; this analysis isalso referred to as own voice recognition or as own voice detection(OVD).

Suitably, the analysis of the respective signal is carried out based onan algorithm or based on one filter or a plurality of filters. Inparticular, the algorithm, the filter or one of the filters is embodiedsuch that when it is applied a signal corresponding to the own voice ofthe wearer is attenuated to the greatest possible extent. Then, withinthe scope of the analysis of the surround signal and/or the auditorycanal signal, the presence of the own voice is deduced based on theabsolute value of the attenuation. Thus, in this case, a sound path fromthe mouth of the wearer to the hearing aid is represented as accuratelyas possible and use is made of a transfer function for the attenuationof the signal which is applicable for this sound path, i.e., whichcorresponds to this sound path.

In this case, the own voice recognition is adaptive. Expresseddifferently, the algorithm or the filter or the filters used to carryout the analysis of the respective signal are adaptable and changeable.In particular, one of the parameters thereof or one of the coefficientsthereof is adaptable and changeable. The algorithm or the filter is set,in particular the parameters thereof and/or the coefficients thereof areadapted, within the scope of training the own voice recognition.Preferably, the algorithm or the filter is set such that the part of theanalyzed signal corresponding to the own voice of the wearer isattenuated more strongly than before the training. As an alternativethereto, the algorithm or the filter is set such that an attenuation, inparticular an absolute value of the attenuation, of the part of theanalyzed signal corresponding to the own voice of the wearer is matchedto a specified value or is made to drop below a specified, and forexample adjustable, threshold.

According to the method, such a training of the adaptive own voicerecognition is controlled based on the (auditory canal) signal, inparticular based on a property of same, output by the auditory canalmicrophone. In particular, the training is started, finished orinterrupted based on the (auditory canal) signal. Provided the traininghas started, a filter or algorithm that was already adapted by apreceding training can also be adapted further. Preferably, the trainingis started or an already started training is continued if the auditorycanal signal or a variable derived from the auditory canal signal,particularly preferably only derived from the auditory canal signal, hasa predefined property.

The invention is based on the discovery that whether the capturedauditory canal signal and optionally the surround signal is suitable fortraining can be determined particularly reliably based on (only) theauditory canal signal. Consequently, the training is implementedparticularly reliably and effectively.

Preferably, in addition to the auditory canal signal, no further signalrecorded by another microphone, in particular the surround signal, isused for determining how the training is controlled.

According to a suitable configuration of the method, the auditory canalsignal is analyzed in respect of the presence of the own voice andprovided the own voice is recognized, the training is startedor—provided the training has already been started—continued. Providedthe own voice is not recognized, no training is started or an alreadystarted training is finished or interrupted (paused). In this case,determining whether the own voice of the wearer of the hearing aid ispresent, i.e., whether the wearer themselves is talking, can be carriedout comparatively reliably based on the auditory canal signal. Thus, aparticularly reliable indicator for the presence of the own voice can beascertained based on the signal.

According to a suitable configuration, the level of the auditory canalsound or a corresponding value of the auditory canal signal is comparedto a given threshold for the analysis of the auditory canal signal inrespect of the presence of the own voice, with different thresholdspossibly being specified for different spectral regions, i.e., fordifferent frequency bands, of the sound or the signal. If the level orthe auditory canal signal exceeds the threshold, the own voice isdeduced and the training is started or continued.

For the purposes of analyzing the auditory canal signal in respect ofthe presence of the own voice, the auditory canal signal isalternatively or additionally examined based on a spectral analysis forfeatures that are characteristic for the own voice of the wearer, saidcharacteristic features for example arising from the sound path throughthe head from the mouth to the auditory canal of the wearer. By way ofexample, an absorption as a function of the frequency is estimated ordetermined to this end.

Further alternatively or additionally, an algorithm or a filter forvoice recognition is applied to the auditory canal signal and anattenuation of same is compared to a specified threshold for theanalysis of the auditory canal signal in respect of the presence of theown voice.

According to an advantageous configuration of the method, the trainingis started and carried out or continued automatically during normaloperation, and hence online. The normal operation should be understoodto mean a mode of operation of the hearing aid which, in particular, ischaracterized by the intended use of the hearing aid for compensating ahearing deficit of the wearer on the basis of processing a soundrecorded by at least one of the microphones and on the basis of theoutput of an appropriate output sound to the ear of the wearer. Inparticular, this does not include speech sequences and/or noisesequences defined in advance for the purposes of training the own voicerecognition.

No process defined by means of a protocol and comprising specifiedspeech sequences is required for the training, in particular foradapting the algorithm or the filter or the filters within the scope ofthe training. Consequently, the training process within the scope ofgeneral fitting at the acoustician or within the scope of a processdefined on the basis of the protocol by the wearer themselves can bedispensed with. Nevertheless, the training may also already take placeduring the fitting session at the acoustician within the scope of anormal conversation, which therefore has no speech sequences and/ornoise sequences defined in advance.

Moreover, to start the training it is no longer necessary for additionalreference information to be transmitted in particular from the user viatheir speech activity by means of an interface, for example a smartphoneor a remote control. In summary, the training of the own voicerecognition is particularly convenient for the wearer.

According to an advantageous configuration of the method, whether theacoustic surroundings of the hearing aid are suitable for the trainingis determined based on the auditory canal signal and/or on the basis ofthe surround signal. In particular, the acoustic surroundings areanalyzed in respect of a noise and/or in respect of a reverberation timeto this end. Depending on the result of this analysis, the training isstarted or still carried out (continued) provided the surroundings weredetermined to be suitable; otherwise the training is finished orpreferably interrupted until the surroundings are determined to besuitable again.

By way of example, a threshold for a noise value, in particular for anoise level, is specified, with the training only being started providedthis threshold was undershot. Suitably, a signal-to-noise ratio, whichis abbreviated SNR, alternatively is determined for the auditory canalsignal and/or for the surround signal and compared to a given threshold.In this case, the threshold is for example 15 dB (decibel), 20 dB or 25dB for the signal-to-noise ratio. If the threshold is exceeded by thesignal-to-noise ratio ascertained from the corresponding signal then thetraining can be started or continued and, expediently, it also isstarted or continued.

In particular, the noise value, in particular the level of the noise inthe acoustic surroundings of the hearing aid, is determined for theauditory canal signal by means of a noise estimator which is based forexample on the “minimum statistics approach”. By way of example, theauditory canal signal itself is used to this end. For a more accuratedetermination of the noise value, the auditory canal signal is initiallyamplified in accordance with a known damping of the signal from thesurroundings by a housing carrying the auditory microphone and/or by adome, and the noise value of the amplified signal is ascertained bymeans of a noise estimator.

Expediently, the noise value for the surround signal is also determinedby means of the noise estimator. Preferably, the training is onlystarted or continued if the noise value of the auditory canal signal andthe noise value of the surround signal are below a specified orrespectively assigned threshold.

As an alternative or in addition to determining the noise value, theacoustic surroundings of the hearing aid are analyzed in respect of areverberation time. Provided the ascertained reverberation time isshorter than a specified threshold of, e.g., less than 500 ms, inparticular less than 300 ms, the training can be started or stillcarried out and it is expediently also started or continued.

This advantageously avoids or least reduces the risk of an unsuitable oreven incorrect training, in particular an unsuitable or incorrectadaptation of the algorithm or of the filter or filters of the own voicerecognition, and so the training is more effective.

Preferably, the acoustic surroundings of the hearing aid are analyzedwhen the own voice was recognized in the manner presented above based onthe auditory canal signal, for example on the basis of the level thereofor on the basis of the spectral analysis thereof. Subsequently—dependingon the result of the analysis of the acoustic surroundings—the trainingis started or still carried out or finished or interrupted until thesurroundings are determined to be suitable again.

According to a suitable development of the method, a convergence value(recognition value) is determined, suitably after the adaptation of thealgorithm or the filter or filters within the scope of the training orafter the training. This convergence value represents a measure or aquality for the recognition of the own voice by means of the own voicerecognition. Furthermore, further training is admitted or the trainingis continued or skipped depending on the convergence value.

By way of example, the absolute value of the damping of the surroundsignal and/or of the auditory canal signal during the application of thealgorithm or the filter or filters for the own voice recognition is usedas convergence value. In this case, the surround signal or the auditorycanal signal substantially corresponds to the signal of the own voicesince, as described above, the training takes place based on theauditory canal signal, and consequently especially when the own voice ispresent, and optionally only in the case of suitable acousticsurroundings.

Expediently, the convergence value is compared to a specified threshold,which suitably corresponds to damping of 15 dB or preferably 20 dB oralternatively 25 dB. If the convergence value is greater than thethreshold, i.e., if a quality of the recognition of the own voice issufficiently high, no further training is admitted or the training isfinished. In a corresponding manner, further training is admitted or thetraining is continued provided the convergence value is less than thethreshold. By way of example, the further training is carried out aftera minimum time period following the preceding training. As analternative thereto, the further training is implemented as soon as theown voice was recognized again based on the auditory canal signal.

According to an advantageous configuration of the method, a malpositionof the auditory canal microphone in the auditory canal and/or of thesurround microphone in or on the ear is determined. Provided suchmalposition was recognized, a further training of the adaptive own voicerecognition is started.

Preferably, the further training in this case is started based on theauditory canal signal, particularly only if the own voice of the wearerwas recognized on the basis of this signal in one of the variantspresented above and/or if the acoustic surroundings of the hearing aidare suitable for the further training.

By way of example, such a malposition occurs when putting on or wearinga pair of spectacles, a hat or a scarf. Here, a malposition should beunderstood to mean a deviation of the position of the auditory canalmicrophone and/or the surround microphone from the position in which theown voice recognition was trained.

By way of example, a sound path from the mouth of the wearer to therespective microphone is changed on account of the malposition. As aconsequence, there is the risk of the algorithm or the filter or filtersof the own voice recognition not correctly representing this sound pathand possibly of errors arising in the detection of the own voice or ofincorrectly determining the noise value. Advantageously, there is a newadaptation of the algorithm or of the filter or filters to the newposition and/or orientation of the respective microphone by the furthertraining following the recognition of a malposition. Consequently, therisk of an incorrect detection of the own voice or an incorrectdetermination of the noise value is at least reduced.

In a suitable configuration of the method, a motion sensor is used fordetermining the malposition of the surround microphone. Said motionsensor is preferably arranged in or on a housing that holds the surroundmicrophone. Suitably, its alignment, in particular the position and/orthe orientation of its axes, can be determined on the basis of themotion sensor. If the motion sensor is rigidly fixed to the housingrigidly holding the surround microphone, a corresponding change in theposition and the orientation of the surround microphone is facilitatedin advantageously simple fashion on the basis of the change in theposition and/or the orientation of the housing.

By way of example, a malposition of the auditory canal microphone isdetermined by analyzing the auditory canal signal. In particular, tothis end, a spectral analysis of this signal is carried out, the signalis examined for changes in the features characteristic for the own voiceand/or the transfer function is examined for changes.

According to the invention, a hearing aid comprises an auditory canalmicrophone and an own voice recognition unit for carrying out anadaptive own voice recognition. In this case, the hearing aid isprovided and set up to carry out the method in one of theabove-described variants. In particular, the own voice recognition unitis embodied such that training for an adaptive own voice recognition isstarted based on a signal output by the auditory canal microphone.

Other features which are considered as characteristic for the inventionare set forth in the appended claims.

Although the invention is illustrated and described herein as embodiedin method for operating a hearing aid, and hearing aid, it isnevertheless not intended to be limited to the details shown, sincevarious modifications and structural changes may be made therein withoutdeparting from the spirit of the invention and within the scope andrange of equivalents of the claims.

The construction and method of operation of the invention, however,together with additional objects and advantages thereof will be bestunderstood from the following description of specific embodiments whenread in connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 schematically shows a hearing aid comprising an auditory canalmicrophone, comprising a surround microphone and comprising an own voicerecognition unit, and

FIG. 2 shows a procedure for operating the hearing aid, in whichtraining of an own voice recognition is started based on a signal outputby the auditory canal microphone.

DETAILED DESCRIPTION OF THE INVENTION

Parts and variables corresponding to one another have always beenprovided with the same reference sign in all figures.

The hearing aid 2 illustrated in FIG. 1 comprises a surround microphone4, based on which sound from the surroundings of the wearer of thehearing aid 2 can be captured. Moreover, the hearing aid 2 comprises anauditory canal microphone 6, which serves to capture sound in theauditory canal 8 of the wearer. To this end, the auditory canalmicrophone 6 is introduced into the auditory canal 8 of the wearer ifthey are wearing the hearing aid 2 as intended. In this case, theauditory canal 8 is only illustrated schematically in FIG. 1 as linesthat are parallel to one another.

According to the embodiment of the hearing aid 2 illustrated in FIG. 1,the latter is embodied as a so-called behind-the-ear hearing aid. Inthis case, the surround microphone 4 is arranged in a housing 10 whichis worn behind the ear, in particular between the auricle of the wearerand their head.

According to an alternative not illustrated in any more detail here, thehearing aid is embodied as an in-the-ear hearing aid, in which both thesurround microphone 4 and the auditory canal microphone 6 are arrangedin a common housing, which is provided and set up for at least partialinsertion into the auditory canal.

The surround microphone 4 and the auditory canal microphone 6 each arean electroacoustic transducer. They convert the respectively capturedsound in the surroundings of the wearer, also referred to as surroundsound for short, and the captured sound in the auditory canal 8, alsoreferred to as auditory canal sound for short, into an electricalsurround signal SU and into an electrical auditory canal signal SG,respectively.

The microphones 4 and 6 are connected to a control unit 12, in which anown voice recognition unit 14 is integrated, for signal transfer. Thus,the own voice recognition unit 14 is a constituent part of the controlunit 12.

Furthermore, the hearing aid 2 comprises a receiver 16, in this case amicro-loudspeaker, which is likewise introduced into the auditory canal8. The receiver 16 is likewise connected to the control unit 12 forsignal transfer, and so a receiver signal SH can be output from thecontrol unit 12 to the receiver. The receiver 16 converts the receiversignal SH into sound and outputs the latter into the auditory canal 8 ofthe wearer.

The hearing aid 2 moreover comprises a motion sensor 18 which isembodied as an acceleration sensor and based on which it is possible todetermine the position and/or the orientation of the hearing aid. Themotion sensor 18 is received in the housing 10 and rigidly joinedtherewith at the location, the surround microphone 4 also being arrangedin said housing.

Here, the own voice recognition unit 14 is set up to carry out an ownvoice recognition. Expressed differently, the surround signal SU and/orthe auditory canal signal SG are analyzed using the own voicerecognition unit 14 in respect of the presence of the own voice of thewearer. In the process, the surround signal SU and/or the auditory canalsignal SG are processed by the control unit 12 or by the own voicerecognition unit 14, the processing depending on whether the own voiceof the wearer was recognized. The receiver signal SH is generated andoutput to the receiver 16 as a result of the processing.

Here, recognition of the own voice by the own voice recognition isimplemented based on an analysis of the signals SU and SG by means of anumber of filters F, i.e., one filter on more than one filter. In thiscase, the filter or filters F have an adaptive embodiment. Consequently,these are changeable or adaptable, especially within the scope oftraining. In summary, the own voice recognition is adaptive. The filteror at least one of the filters F is embodied in such a way in theprocess that, if applied, a signal corresponding to the own voice of thecarrier or to the part of a signal to be analyzed which corresponds tothe own voice is attenuated to the greatest possible extent. Thus, asignal SU or SG analyzed based on this filter F is subject to moreattenuation, the more said signal corresponds to the own voice of thewearer.

According to an alternative not illustrated in any more detail here, analgorithm that analyzes the signals SU and/or SG is used in analogousfashion for the recognition of the own voice.

The own voice recognition unit 14 is embodied such that training of theadaptive own voice recognition is started based on the signal SG outputby the auditory canal microphone 6, as illustrated in more detail belowbased on FIG. 2.

It is evident from FIG. 2 that the training is implemented during normaloperation N. In this case, the auditory canal signal SG and/or thesurround signal SU is processed, in particular continuously, by thecontrol unit 12 or by the own voice recognition unit 14 and is output tothe receiver 16 as receiver signal SH for compensating a hearing deficitof the wearer.

The signal SG output by the auditory canal microphone 6, whichcorresponds to or represents the sound in the auditory canal 8 of thewearer, is transmitted to the control unit 12, specifically to the ownvoice recognition unit 14 (step I).

In a second step II, the auditory canal signal SG is analyzed in respectof the presence of the own voice using the own voice recognition unit14. To this end, the level P of the auditory canal sound is compared toa given threshold based on the auditory canal signal SG or acorresponding value of the auditory canal signal SG. The own voice ofthe wearer is considered identified should this threshold be exceeded.

Additionally, for the purposes of analyzing the auditory canal signal SGin respect of the presence of the own voice, a spectral analysis inrespect of at least one feature M characteristic for the own voice ofthe wearer is carried out for the auditory canal signal SG.

Furthermore, a filter F1 of the number of filters F of the speechrecognition is applied to the auditory canal signal SG and anattenuation of the latter is compared to a specified threshold for the(redundant) analysis as to whether the own voice of the wearer ispresent. The presence of the own voice is deduced should the attenuationbe greater than the threshold.

According to alternatives not illustrated in any more detail, only oneor two of the processes presented above, i.e., determining a level ofthe signal SG, the spectral analysis thereof or the application of afilter to this signal SG, is used for the analysis of the signal SG inrespect of the presence of the own voice.

Preferably, the remainder of the method is only carried out if the ownvoice of the carrier was recognized in step II.

In a third step III of the method, which follows the second step intime, the auditory canal signal SG is used to determine whether theacoustic surroundings of the hearing aid 2 are suitable for training. Tothis end, the acoustic surroundings are analyzed in respect of a noiseand in respect of a reverberation time tN.

To this end, a signal-to-noise ratio SNR is determined for the auditorycanal signal SG and is compared to a specified threshold. In this case,the noise is determined by means of a noise estimator.

According to an alternative not illustrated in any more detail, asignal-to-noise ratio SNR is also determined by means of the noiseestimator for the surround signal SU.

If the own voice is recognized as per step II, if the specifiedthreshold is exceeded by the signal-to-noise ratio SNR of the auditorycanal signal SG, optionally if the threshold is exceeded by thesignal-to-noise ratio SNR for the surround signal SU, and in the case ofa reverberation time tN that is shorter than a further given threshold,the training of the adaptive own voice recognition is started or, shouldtraining have already been started, the latter is continued. Within thescope of the training (step IV), the filter or filters of the own voicerecognition are altered.

A convergence value K, which is a measure for the recognition of the ownvoice by means of the own voice recognition, is determined in a fifthstep V. Here, the absolute value of the attenuation (damping) of thesurround signal SU and/or of the auditory canal signal SG when applyingthe filter or filters F of the own voice recognition is used asconvergence value K. Further training is admitted if the convergencevalue K is smaller than a further specified threshold TK; this isillustrated in FIG. 2 based on the arrow from step V to step I. Shouldthe convergence value K be greater than the threshold TK, the trainingis finished and there is no further training, i.e., the further trainingis omitted.

In a sixth step VI, a position of the surround microphone 4 isdetermined based on the signal SB of the motion sensor 18. In this case,signals SB are output from the motion sensor 18 to the control unit 12.They are evaluated by the control unit 12 in respect of their relativeposition and in respect of their orientation and consequently in respectof the relative position and orientation of the surround microphone 4and the housing 10. Should a malposition be identified, i.e. a deviationof the position and/or the orientation of the surround microphone fromthe position in which the own voice recognition was trained earlier intime, the above-described method is carried out again from step I, with,therefore, there being a further training of the own voice recognition.This also occurs should a previously determined convergence value K begreater than the threshold TK. This at least reduces the risk of anincorrect detection of the own voice or incorrect determination onaccount of the malposition.

Determining whether a malposition is present as per step VI isimplemented automatically during the normal operation N in this case.This occurs recurrently here after a specified time interval, forexample every 30 seconds.

In summary, the training of the adaptive own voice recognition iscontrolled based on the signal SG output by the auditory canalmicrophone 6. Determining whether the training is started or continuedis implemented automatically in this case, i.e., without an input by theuser.

The invention is not restricted to the above-described exemplaryembodiment. Rather, other variants of the invention can also be derivedfrom this by a person skilled in the art without departing from thesubject matter of the invention. In particular, all individual featuresdescribed in the context of the exemplary embodiment are further alsocombinable with one another in a different way without departing fromthe subject matter of the invention.

The following is a summary list of reference numerals and thecorresponding structure used in the above description of the invention:

LIST OF REFERENCE SIGNS

-   2 Hearing aid-   4 Surround microphone-   6 Auditory canal microphone-   8 Auditory canal-   10 Housing-   12 Control unit-   14 Own voice recognition unit-   16 Receiver-   18 Motion sensor-   I Output of the auditory canal signal to the own voice recognition    unit-   II Analysis in respect of the own voice-   III Evaluation of the surroundings of the hearing aid-   IV Training-   V Determination of the convergence value-   VI Determination of a malposition of the surround microphone-   F,F1 Filter-   K Convergence value-   M Feature of the own voice-   N Normal operation of the hearing aid-   P Level-   SNR Signal-to-noise ratio-   SB Signal of the motion sensor-   SG Auditory canal signal-   SH Receiver signal-   SU Surround signal-   tN Reverberation time

1. A method for operating a hearing aid, the method comprising:providing an auditory canal microphone configured for capturing sound inthe auditory canal of a wearer; providing an own voice recognition unitconfigured for carrying out an adaptive own voice recognition; capturingsound in the auditory canal by the auditory canal microphone;outputting, by the auditory canal microphone, an auditory canal signalthat corresponds to the sound in the auditory canal; and controlling, bystarting, continuing, finishing, or interrupting, a training of theadaptive own voice recognition only based on the signal output by theauditory canal microphone.
 2. The method according to claim 1, themethod further comprises: analyzing the auditory canal signal in respectto the presence of the own voice; starting or continuing the training ifthe own voice is recognized; not starting the training, or finishing orinterrupting an already started training, if the own voice is notrecognized.
 3. The method according to claim 2, wherein the step ofanalyzing the auditory canal signal in respect to the presence of theown voice comprises: determining a level of the auditory canal signal;examining the auditory canal signal based on a spectral analysis forfeatures that are characteristic of the own voice of the wearer, and/orapplying a voice recognition filter to the auditory canal signal.
 4. Themethod according to claim 1, wherein the training is startedautomatically during a normal operation.
 5. The method according toclaim 1, the method further comprises using the auditory canal signalfor determining whether surroundings are suitable for training.
 6. Themethod according to claim 5, wherein the suitability of the surroundingsis based on a noise and/or in respect to a reverberation time in thesignal of the auditory canal microphone.
 7. The method according toclaim 5, the method further comprises determining a noise value based onthe signal of the auditory canal microphone.
 8. The method according toclaim 1, the method further comprises: determining a convergence valuewhich represents a measure or quality for recognizing the own voice bymeans of the own voice recognition; and admitting or omitting a furthertraining depending on the convergence value.
 9. The method according toclaim 1, the method further comprises: detecting a malposition of theauditory canal microphone and/or a surround microphone; and starting afurther training of the adaptive own voice recognition if a malpositionwas detected.
 10. The method according to claim 9, the method furthercomprises providing a motion sensor configured to determine malpositionof the surround microphone.
 11. A hearing aid comprising: an auditorycanal microphone; an own voice recognition unit configured to carry outan adaptive own voice recognition; and said own voice recognition unitbeing configured to start a training of said adaptive own voicerecognition based on a signal output by said auditory canal microphone.